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Tsirkin" , Peter Xu , Eduardo Habkost , Marcel Apfelbaum , Yanan Wang , Michal Privoznik , =?UTF-8?Q?Daniel_P_=2e_Berrang=c3=a9?= , Gavin Shan , Alex Williamson , Stefan Hajnoczi , "Maciej S . Szmigiero" , kvm@vger.kernel.org References: <20230825132149.366064-1-david@redhat.com> <20230825132149.366064-17-david@redhat.com> From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= In-Reply-To: <20230825132149.366064-17-david@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2a00:1450:4864:20::335; envelope-from=philmd@linaro.org; helo=mail-wm1-x335.google.com X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-2.169, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 25/8/23 15:21, David Hildenbrand wrote: > Let's mark the memslot alias memory regions as unmergable, such that > flatview and vhost won't merge adjacent memory region aliases and we can > atomically map/unmap individual aliases without affecting adjacent > alias memory regions. > > This handles vhost and vfio in multiple-memslot mode correctly (which do > not support atomic memslot updates) and avoids the temporary removal of > large memslots, which can be an expensive operation. For example, vfio > might have to unpin + repin a lot of memory, which is undesired. > > Signed-off-by: David Hildenbrand > --- > hw/virtio/virtio-mem.c | 6 ++++++ > 1 file changed, 6 insertions(+) Reviewed-by: Philippe Mathieu-Daudé